Oil, natural gas, and other hydrocarbons are obtained by drilling wells into the earth and forcing them to the surface for collection. It is often difficult to produce hydrocarbons in an economic manner from low permeability reservoir rocks. Production rates are often boosted by resorting to hydraulic fracturing, a technique that increases rock permeability by opening channels through which hydrocarbons can flow to recovery wells. During hydraulic fracturing, a fluid is pumped into the earth under high pressure where it enters a reservoir rock and cracks or fractures it. Proppants are carried in a suspension by the pumped fluid into the fractures. When the pressure is released, the fractures partially close on the proppants, leaving channels for oil and gas to flow. Specialized pumps are used to develop the pressures necessary to complete a hydraulic fracturing procedure or “frac job.”
Specialized pumps are also used in other drilling pump applications. For instance, during drilling of the well hole into the earth, specialized pumps are used to flush out the hole. Flush out is important to remove debris, such as rock chips ground out by the drill bit during drilling.
These specialized pumps are usually provided with fluid ends having reciprocating plungers or pistons that place fluids under pressure and valves that control fluid flow to and from the plungers. The body of a fluid end can be a metal forging of steel, having a “Y-type” configuration.
Y-type fluid ends have been developed in an effort to reduce the number of failures of fluid ends. It is known, Y-type fluid ends reduce concentrated stresses in the body of a fluid end by increasing the angles at which bores within the body intersect one-another above 90 degrees to about 120 degrees. A typical Y-type fluid end is disclosed in U.S. Patent Application Publication No. US 2004/0234404, now abandoned, which is incorporated herein by reference.
Y-type fluid ends require periodic replacement due to the loads placed on the portions of the end such as the suction deck. The valves also have to be frequently replaced.